Ask the Experts about Jewelry Making

Topics: Metal Clay, Firing

Q.

I just bought a new kiln and have tried the time and temperature listed, but my pieces are coming out not completely fired. How do I adjust the time and temperature without ruining more silver and copper clay?

- Audra

A.

Each kiln fires differently, and results can vary according to ramp times and where the pieces are placed in the firing pan (for PMC PRO™, BRONZclay™ and COPPRclay™) or on the kiln shelf (for fine silver metal clay). Each clay package comes with firing instructions. It's very important to follow the manufacturer's instructions and to consider doing a test fire first, before you fire a full kiln load of your creations.

Firing fine silver metal clay, following manufacturer's recommendations, is very reliable. When firing the other metal clays, you need to follow their guidelines but also become very familiar with your kiln and how it works within the guidelines offered in each package of clay.

If your pieces are not fired, or sintered properly, it would be advisable to increase both temperature and soak time. The higher temperature will sinter the metal properly and the longer soak time will allow the molecules to fuse together for a better overall structure. Each manufacturer offers a maximum firing temperature so you do not reach the metal's melting point--this temperature is established based on the knowledge that some kilns will fire hotter; it is a good idea not to go above this recommended temperature until you know your kiln well. It is also very important that you not go over the highest temperature recommended for any inclusions you may have in your designs.